If the whole earth is to be connected by LOS communication using space waves (no restriction of antenna size or tower height), what is the minimum number of antennas required? Calculate the tower height of these antennas in terms of earth's radius.?

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Alok Kumar Singh | Contributor-Level 10

10 months ago

This is a Short Answer Type Questions as classified in NCERT Exemplar

maximun distance to cover entire surface of earth for communication is

d_m²= (R+h)²+ (R+h)²= 2 (R+h)²

So d_m= $\sqrt[]{2 h R} + \sqrt[]{2 h R} = 2 \sqrt[]{2 h R}$

8hR= R²+2Rh+h²

R-h=0

R=h so frequency of space wave Is less than height of tower. So it is also keep in consideration. for 3

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